A rail vehicle is equipped with for example a plurality of motors that drive the vehicle (that is to say, wheels) and air conditioning equipment and the like, and drive control equipment that controls the motors. The drive control equipment comprises a power conversion device such as a converter that converts AC voltage supplied from the power source to DC voltage and outputs the DC voltage to a motor, or an inverter that converts DC voltage to three-phase AC voltage and outputs the three-phase AC voltage to a motor, and a control device that controls the power conversion device and the motors. In addition, the drive control equipment comprises for example a contactor or breaker connected between the power conversion device and the motor. The contactor opens and closes the connection of the power conversion device and the motor: it opens the connection for example on stoppage of operation by the drive control equipment or in the event of abnormality. An example of such a thing is disclosed in Japanese Patent Number 4297971 (hereinafter referred to as Patent Reference 1).
In recent years, permanent magnet synchronous motors are being employed as motors for rail vehicles. Permanent magnet synchronous motors have the advantage of high efficiency, compared with induction motors. However, permanent magnet synchronous motors require a driving inverter for each motor. In the case of a rail vehicle, an arrangement is adopted in which each vehicle is driven by a group of a plurality of motors, so, in the drive control equipment used to drive the plurality of motors, the number of inverters required must be increased, together with increase in the number of elements and increase in the number of contactors. This results in large external dimensions and mass of the drive control equipment, increasing manufacturing costs.
The present invention was made in view of the foregoing, the problem of the invention being to provide drive control equipment for a rail vehicle in which increase in size of the equipment can be restricted and manufacturing costs can be reduced.
In this embodiment, vehicle drive control equipment for driving a plurality of motors provided in a vehicle has the following construction. Specifically, it comprises:
a plurality of power conversion devices respectively connected to a plurality of motors provided in a vehicle, that convert a DC power that is supplied from a DC power source to AC power and output the AC power to the motors;
a control device that controls said power conversion devices;
a frame, having a ceiling wall facing a floor of the vehicle, a bottom wall facing a ground, and a sidewall connecting the ceiling wall and the bottom wall, that accommodates the power conversion devices and the control device; and
a power unit having a cooler in which are mounted a plurality of semiconductor elements constituting the power conversion devices, a first control board having a first connector connected with the semiconductor elements, arranged facing the cooler, and a second control board having a second connector connected with the first connector of the first control board, arranged a direction orthogonal to the first control board.